Strand-former balloon control



April 21, 1953 J. A. TRUlTT I 2,635,413

STRAND-FORMER BALLOON CONTROL Filed May 18, 1949 2 SHEETS-SHEET 1 INVENTOR. JOSEPH A. TRU/TT hwm' y ATTORNEY April 1953 J. A. TRUlTT 2,635,413

STRAND-FORMER BALLOON CONTROL Filed May 18, 1949 2 SHEETSSHEET 2 INVENTOR. JOSEPH A. TRU/TT ATTORNEY Patented Apr. 21, 1953 UNITED STATES PATENT ()FFICE American Viscose Corporation,

Wilmington,

Del., a corporation of izelaware Application May 18, 1949, Serial No. 93,939

20 Claims.

This invention relates to the control of twisting devices, and particularly with controlling the balloons formed thereby, of the multiple-twist down-twister type, such as a two-for-one downtwister, for forming a strand from two or more continuous bundles of filamentary material and collecting the double strand as a wound package on the down twister. The term strand as used herein applies to continuous fibrous or filamentary bundles of textile material such as yarn, thread, cord of single or doubled structure of any type which may be passed through twisting machinery.

In a strand-former of this type heretofore used, the primary strands are brought together and pass through a constant speed positive drawing device before entering the balloon of the down-twister. The strands, as they pass into this balloon are twisted into a cord, a doubled yarn, or a piled strand. The resulting composite strand enters the rotary portion of the twister through a flyer, passes through the bore of the hollow spindle shaft carrying the fiyer to a region above one end of the package, and then is led over pulleys to a traversing mechanism. The pulleys and the traversing mechanism are supported by a cage mounted exteriorly and independently of the package holder of the machine.

- The traversing mechanism feeds the cord into the rotating package from a reciprocating position moving in a direction parallel with the package axis. The rotation of the package is ordinarily obtained by means of a slip-clutch, such as'a magnetic drive, of which a driving member is fixed to the spindle shaft and a driven member is fixed to the package holder. The drive is adjusted to transmit torque which maintains a desired tension in the cord while permitting slipping, or slower rotation, of the package holder with respect to the spindle shaft in'order to wind onto the package the cord delivered by the drawing-ofi" device.

However, in the conventional system, the tension in the cord being pulled through the cording balloon and collected on the package changes in inverse proportion to the radius of thepackage during winding; this radius, of course, represents the length of the moment arm applied by the package to the cord.

Attempts to increase the torque applied to the package holder (and thereby indirectly to the cord being wound thereon) as the diameter of the package increases in the hope of maintaining uniform cord tension and thereby a desired balloon shape in the strand doubler have met with little success because of many other complicating factors which affect the stability of the balloon such as cyclic variations which may develop in the movement of the cord through the balloon. Such irregularities in the building of a cord package produce a package lacking uniformity in density and degree of twist. Most important, however, is that lack of contro1 of the balloon causes excessive tension which produces broken filaments, or too little balloon tension which permits the balloon to explode.

It is a principal object of the invention to provide a method and mechanism for controlling the balloon of the strand prior to its collection as a wound package on a twister. It is another object to provide an apparatus for producing a strand package having uniform density and degree of twisting. It is still another object of the invention to provide means accomplishin these objects adaptable to conventional twisting machincry of the mutliple twist type. Other objects, features, and advantages will be apparent in the ensuing description of the invention and the drawings relating thereto in which Fig. 1 is an elevation in section of a cord twister system of the invention;

Fig. 2 is a pictorial view of a tension-regulating mechanism of the machine illustrated in Fig. 1;

Fig. 3 is an end view of the mechanism illustrated in Fig. 2;

Fig. 4 is a fragmentary pictorial view of a traverse mechanism that may be used on the machine of Fig. 1; and

Fig. 5 is a plan view illustrating an arrangement for driving the various twisting units of the machine partly illustrated in Fig. 1.

According to the invention, when two or more strands are twisted or doubled into a single cord or plied strand, the smaller strand are passed prior to the doubling operation through a mechanism which prevents them from slipping longitudinally with respect to each other and the mechanism, and imposes a restraining force on them which opposes the tension existing in the cord within the rotating balloon in the cord twister. The restraining force is obtained by such means as passing the strands around a roll in as many laps as are necessary to prevent slipping when a brake is applied to the roll or other rotary parts connected therewith. A single drawing means such as capstan rolls rotatably mounted on a non-rotating portion of the cord twister and hereinafte described, is used to draw the cord through the secondary twisting system as well as through the primary twisting systems for individually twisting the separate strands which together form the cord as they pass into the secondary system, and to deliver the cord to a traverse mechanism for feeding the cord onto a takeup bobbin included within the secondary system. The drawing means is positively driven from the spindle shaft of the cord twister, in order that the speed of strand take-up may be held in constant ratio with the spindle speed.

Figure 1 is a section view of the twisting machine taken along a plane passing through the axes of two supply twisters 8 and 9 and an intermediate cord twister H) which receives the strands from the supply twisters. These twisters may comprise merely one or two or more sets of such twisting units of a single machine. A plan view of a driving arrangement for a machine comprising two sets of the units is shown in Fig. 5. Strands are pulled from the conventional two-for-one twisters 8 and 9 and guided to the regulating device l2. The two strands i4 and I are led around a drum surface I! (refer to Fig. 2) through several turns in order to provide suificient contact between the strands and the surface of the device |2 to prevent slipping of the strands thereon while subjected to the excess of the tension produced in the cord in the balloon over the sum of similar opposing tensions in the balloons of twisters 8 and 9. The various tensions in the balloons result from the action of the drawing device mounted on the cord twister l0 and the centrifugal forces set up in the several balloons. The strands l4 and I5 are passed from the surface I! through a guide l8 and become twisted as they leave the drum surface to form a strand or cord 2| of doubled construction which enters the balloon 20. The cord 2| enters a fiyer 23 and passes into and through a hollow spindle shaft 24 toward the top of the twister H1.

The twister I0 is of the take-up package-building or down-twisting type comprising three principal rotatably independent structures, the first of which is the positively driven assembly comprising the spindle shaft 24, the flyer 23 and the driving member 21 of a magnetic clutch for driving a package holder 29.

The second structure of the twister is the package holder 29 supported coaxially and rotatably on the spindle shaft 24 by bearings 3| and 32. The driven member 34 of the magnetic clutch is secured to the lower portion of th holder 28 and spaced from the element 21 to produce a gap 35 having sufficient width to result in the desired degree of slippage of the package holder with respect to the spindle shaft. By this arrangement, sufiicient torque is transmitted to the package holder to cause it to operate as a takeup means for cord delivered to it through a traverse mechanism 31.

The third structure of the twister I0 is a cage rotatably supported on the spindle shaft 24 at bearing 4|. It is prevented from rotating, however, by a weight 43 which positions the cage 40 according to the inclination from the vertical of the spindle shaft 24. In a twisting machine such as being described, the axes of the spindles are canted a few degrees from the vertical in a direction such that as viewed in Fig. 1, the upper portions of the spindle shafts are toward the observer. For the purposes of illustration, the weight 43 is shown in section in Fig. 1. The normal position of this weight during operation is controlled by the inclination of the spindle 24 and is disposed approximately 90 degrees with respect to the axis of the spindle 24 from the position shown. The cage 40 includes also a removable cap 45 secured to a ring 48 of the cage during operation. Th cap 45 has a central hub portion 41 which extends into the end of an upwardly extending hub portion 48 of the package holder 29. A bearing 48 is provided between the hub portions 41 and 48 to permit frictionless rotation of the package holder 29 and the hub 48 thereof with respect to the cap 45. A shaft 50 extends through the hub 41 and turns with the spindle shaft 24 in consequence of their adjacent ends being positively coupled. The end portion of the shaft 50 protruding through the cap 45 is supported laterally within the cap by a bearing 5| and is provided with a pulley 52 of small diameter for driving, by means of the belt shown thereabout, a pulley 53 of much larger diameter secured to the shaft of capstan roll 55. A bracket 51 serves as a bearing means for the shaft extending through the roll 55 and the pulley 53, and also as a bearing for a shaft of the freely rotatable capstan roll 58. The rolls 55 and 58 are provided with a plurality of spaced circumferential grooves which guide the strand 2| progressively through a series of spaced convolutions about the rolls. The strand is thus advanced in a, longitudinal direction over the roll surfaces so as to avoid abrasion of the cord or strand. The roll surfaces may be of progressively reduced diameter to allow relaxation of the cord tension in passing around the rolls. If a greater or lesser rate of yarn take-up is desired, the diameter of the capstan roll 55 driven from the spindle axle may be changed to provide the desired ratio of peripheral speed of the roll with respect to the rotation of the spindle. A change in ratio may also be accomplished by changing the relative sizes of pulleys, or gears, etc., used in the drive-connection between the spindle and the capstan rolls, such as in the relative sizes of the pulleys 52 and 53.

The cord 2| passes from the bore of the shaft 50 over a guide pulley B0 and around the rolls 55 and 58. In consequence of the contact of the convolutions with the rolls 55 and 58, gripping power is obtained to such an extent that the rolls become a positive drawing means for the cord. The cord, which is discharged at a constant rate (or a rate which varies with the spindle speed) from the rolls and passed over the pulley 82, is maintained in a taut condition as a result of its being pulled while being collected on the surface of the package 84 by the tangential force exerted at said surface produced by torque acting on the package holder 34 through the magnetic clutch. However, irregularities in tension produced in the balloon 25 arising from the rotation or motion of the package 84 and the holder do not produce slippage of the cord about the rolls 55 and 58 and therefore cannot be transmitted to the balloon. As a result of the constant pull applied to the cord 2| in the balloon 20 by the rolls 55 and 58, the tension can be controlled by a restraining force imposed at the device |2 on the cord, or the strands of which the cord is comprised.

Tension is imparted to the cord passing through balloon 20 by the device l2, best shown in Figs. 2 and 3, wherein a plurality of strands may be gathered upon the drum surface I! and discharged as a group of strands which when twisted become the cord 2|. The drum Ila is secured to a shaft 66 supporting also a brake drum 81 secured thereto. A brake shoe 59 engages the surface of the drum 6! according to predetermined pressure applied through a lever 10 from a tension spring 12. The pressure may be varied by adjustable means such as a wing nut 14 and the threaded rod 15 to which one end of the spring 12 is secured. The braking arrangement illustrated and described with respect to the device 12 is merely an example of the conventional braking systems of which such others as the fluid-coupling, magnetic and centrifugal types may be readily substituted.

The thread is distributed upon the package 64 in helically arranged convolutions spaced longitudinally with respect to the package axis by a conventional traverse mechanism, an example of which is illustrated in Fig. 4 wherein is shown a cam surface as protruding from the circle formed by a peripheral surface (the projection of which isindicated by the dotted line 82) of the package holder 29. The cam surface 80 engages the head 83 of a plunger 86 which recip-rocates within a guide 35. The end of the plunger 86 opposite the head 83 is pivotably connected to a lever 88 which may pivot about a shaft 9!]. A pawl 92 is pivotably secured to the'lever 88 and engages the ratchet wheel 93 secured to the shaft 90. A spring 95 holds the pawl in engagement with the ratchet surface of the wheel 93. The spring 98 holds the plunger in contact with the periphery of the package holder base. package holder in either direction, therefore, results in operation of the ratchet device and rotation of the shaft 9% in the direction indicated by the arrow. The shaft 80 is provided with a reversible thread to drive the traverse element 98 in reciprocating motion with respect to the shaft 90 and a guide rod 99.

Fig. 5 is a plan view of an arrangement for driving two sets of twisting units of a commercial machine which may produce two doubled strands simultaneously. Motors H drive belts I92 which pass around the pulleys of the twisters l0, 8, and 9 in the manner shown.

The invention herein described may be applied to any twisting machinery requiring the formation of a balloon in the strand being twisted. It is of particular utility in closely regulating and stabilizing the forces affecting the formation of the balloon in the strand passing into a strand former or doubler. Although the passing of the strands through several turns about the drum surface I? brings about parallelism andeliminates lengthwise movement in the strands with respect to each other preparatory to entering the twisting zone, the characteristics of the doubled strand may be improved by regulating each of the strands to approximately the same tension before passing from the twisting unit of each strand. For example, the tension may be regulated in the twisting units 8 and 9 by varying the weight and size of the ball 15 under which the strand passes to enter the hollow shaft of the unit.

While a preferred embodiment of the invention has been shown, it is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. In combination in a strand-forming machine, a plurality of singles twisters, means for doubling a plurality of strands into a plied strand, said doubling means having a hollow rotatable spindle, a rotatable member positioned between the singles twisters and doubling means having Rotation of the an annular surface for receiving the strands from the twisters and passing them as a group to the doubling means, brake means for controlling the rotation of the rotatable member, a pair of thread-advancing rolls for drawing the plied strand from the singles system into the doubling means mounted on the doubling means and disposed to receive plied strand from the bore of the hollow spindle, means for connecting the spindle and at least one of the rolls in positive driving relationship.

2. A combination as defined in claim 1 wherein the doubling means comprises a hollow spindle having a flyer attached, a package holder rotatably supported on the spindle, a cage surrounding the package holder and the space occupied by a full package and rotatably supported on the spindle, means for restraining rotation of the cage, a slip-clutch for permitting relative rotation between a driving and a driven member while transmitting a predetermined torque between the members, said driving member being supported non-rotatably and concentrically on the spindle, and the driven member of the clutch secured to the package holder concentrically with respect to the spindle at a predetermined clearance with the driving clutch member.

3. A combination as defined in claim 2 wherein a package building traverse mechanism is sup ported by the cage, and meansfor connecting the traverse mechanism and the package holder in driving relationship.

4. A combination as defined in claim 2 wherein the spindle axis is inclined from the vertical and the means used to restrain the rotation of the cage is a weight secured to one side of the cage.

5. A combination as defined in claim 2 wherein the clutch is of the magnetic-type comprising members which contain magnetic elements cooperating to produce magnetic force between the members.

, 6. In combination in a strand-twister, a driven drum surface for receiving a plurality of strands and discharging them as a single group having sufficient area to support windings of the strand passed therearound to prevent slippage therewith, adjustable brake means for restraining the rotation of the drum surf-ace and for controlling the tension in the group of strands discharged from the surface, a device for twisting the strands into a single filamentary bundle comprising a hollow spindle shaft, a fiyer secured thereto for receiving the strands, a package holder supported coaxially and rotatably independently about the spindle shaft, a slip-clutch having a driving member attached to the spindle shaft and a driven member attached to the package holder, a nonrotatable cage extending around the package holder and a strand package supported thereupon, a pair of capstan rolls rotatably attached to the upper portion of the cage, a hollow shaft extending from the spindle shaft in axial alignment therewith and passing through the upper portion of the cage, means for connecting the hollow shaft and at least one of the rolls in driving relationship, and a traverse guide for delivering the strand discharged from the capstan rolls to the package holder from a path of reciprocation extending lengthwise of the region occupied by a package supported on the holder.

7. In combination, in a strand-forming machine comprising a plurality of singles twisters, means for doubling a plurality of strands into a plied strand, said doubling means having a hollow rotatable spindle, tension-producing retarding means positioned between the singles twisters and the doubling means for collecting strands passing from the twisters to the doubling means into a group and discharging the group under uniform tension, a rotatable thread-advancing roll for drawing the plied strand into the doubling means, said roll mounted on the doubling means and disposed to receive the plied strand from the bore of the hollow spindle, a hollow axial extension of the spindle, and means connecting the roll and the spindle extension in positive driving relationship.

8. In combination, in a strand-forming machine comprising a plurality of singles twisters, means for doubling a plurality of strands into a plied strand, said doubling means having a hollow rotatable spindle, a roll rotatably supported between the singles twisters and the doubling means for collecting strands passing from the twisters to the doubling means into a group, said roll being driven solely by the strands, brake means for retarding the rotation of the roll, a rotatable thread-advancing roll for drawing the plied strand into the doubling means, the lastmentioned roll being mounted on the doubling means and disposed to receive the plied strand from the bore of the hollow spindle, a hollow axial extension of the spindle, and means connecting the roll and the spindle extension in positive driving relationship.

9. An apparatus for forming stranded cord from a plurality of threads comprising a plurality of sources of threads, means for gathering the threads fed from their sources, the last named means including a sheave, means for retarding the rotation of the sheave, thread from each source being led under substantially equal tension to and around the sheave, a cabling device of the type creatingand receiving material from, a balloon for twisting together the threads to form a cord, said cabling device comprising a rotary driven spindle having a free end spaced from the sheave, the sheave lying at least generally on the projected axis of the spindle, a bobbin support mounted on the free end of such spindle, a slip driving connection between the spindle and the bobbin support, a cord guide supporting structure spaced radially of the bobbin support, a twisting disc mounted on the spindle for rotation therewith, the spindle having an axial passage in its free end, the twisting disc having a substantially radial passage therethrough and connecting with the passage in the spindle, the cord guide supporting structure having a cord guiding and loading device thereon, driven means on the apparatus for engaging the cord, in its passage through the device, at a location between the outer end of the radial passage in the twisting disc and the cord guiding and loading device, said last named means substantially posi tively forwarding the cord, and means for driving said last named means in synchronism with the spindle, said driven cord engaging means be-- ing the sole source of power to forward the cord from the balloon of the cabling device and to overcome the retarding effect of the sheave. whereby cord fed from the sheave, through the balloon of the cabling device and thence through the passageways in the twisting disc and the spindle, to the guiding and loading device on the cord guide supporting structure, and thence to the bobbin, is given a double twist when the spindle is rotated and the cord is wound on the bobbin.

10. An apparatus for forming stranded cord from a plurality of yarns in one continuous operation, comprising a plurality of similar twisting spindles each incorporating its source of yarn supply, the spindles being of the type which delivers the twisted thread therefrom in a balloon, means incorporated in each twisting spindle for imposing a predetermined back tension on the yarn, the axis of each such balloon generally 00- inciding with the axis of its spindle, the axes of the twisting spindles being generally parallel, means for gathering the threads from the twisting spindles, the last named means including a sheave, means for retarding the rotation of the sheave, thread from each twisting spindle being led under tension from its balloon substantially directly to and around the sheave, such sheave being located beyond the outer end of each of the balloons from the twisting spindles and being spaced at substantially equal distances from the axes of the spindles, a cabling device of the type creating, and receiving material from, a balloon for twisting together the thus forwarded threads to form a cord, said cabling device comprising a rotary driven spindle having a free end spaced from the sheave, the sheave lying at least generally on the projected axis of the spindle, 9. bobbin support mounted on the free end of such spindle, a slip driving connection between the spindle and the bobbin support, a cord guide supporting structure spaced radially of the bobbin support, a twisting disc mounted on the spindle f or rotation therewith, the spindle having an axial passage in its free end, the twisting disc having a substantially radial passage therethrough and connecting with the passage in the spindle, the cord guide supporting structure having a cord guiding and loading device thereon, driven means on the apparatus for engaging the cord, in its passage through the device, at a location between the outer end of the radial passage in the twisting disc and the cord guiding and loading device, said last named means substantially positively forwarding the cord, and means for drivin said last named means in synchronism with the spindle, said driven cord engaging means being the sole source of power to forward the cord from the balloon of the cabling device and to overcome the retarding effect of the sheave, whereby cord fed from the sheave, through the balloon of the cabling device and thence through the passageways in the twisting disc and the spindle, to the guiding and loading device on the cord guide supporting structure, and thence to the bobbin, is given a double twist when the spindle is rotated and the cord is wound on the bobbin.

11. The method of forming stranded cord from a plurality of threads comprising the following steps in the order named: feeding each of a plurality of threads in the direction of its length from its separate source of supply, imposing a predetermined back tension on each such thread, gathering such threads into generally parallel relationship, forwarding such threads in such generally parallel relationship, twisting the thus fed gathered threads together to form a cord, during the last named twisting step forming a balloon in the cord, positively withdrawing the twisted cord from the last named balloon at a rate synchronized with the rate of twisting of the threads together, the positive withdrawing of the cord from the last named balloon serving as the sole power for drawing the threads from their sources and for withdrawing the cord from its balloon, and yieldingly coiling such cord, the gathering of the threads and the cord twisting and reeling steps being performed with the material continuously in motion.

12. The method of forming stranded cord from a plurality of threads comprising the following steps in the order named: feeding each of a plurality of threads in the direction of its length from its separate source of supply, imposing a predetermined back tension on each such thread, gathering such threads into generally parallel relationship and retarding their travel at the point of gathering, forwarding such threads in such generally parallel relationship, twisting the thus fed gathered threads together to form a cord, during the last named twisting step forming a balloon in the cord, positively withdrawing the twisted cord from the last named balloon at a rate synchronized with the rate of twisting of the threads together, the positive withdrawing of the cord from the last named balloon serving as the sole power for drawing the threads from their sources, for overcoming the retarding force imposed on them at their point of gathering, and for withdrawing the cord from its balloon, and yieldingly coiling such cord, the gathering of the threads and the cord twisting and reeling steps being performed with the material continuously in motion.

13. The method of forming stranded cord from a plurality of yarns in one continuous operation comprising the following steps in the order named: feeding each of a plurality of yarns in the direction of its length from its separate source of supply, imposing a predetermined back tension on each such yarn, forming a balloon in each such yarn and separately twisting the yarns to form threads, the axis of the balloon in each yarn extending in generally the same direction as that of each of the other yarns, gathering such threads into generally parallel relationship and retarding their travel at a point beyond the balloon in each, the location of gathering and retardation of the threads being substantially the same distance from the outer end of each balloon, forwarding such threads in such generally parallel relationship, twisting the thus fed gathered threads together to form a cord, during the last named twisting step forming a balloon in the cord, positively withdrawing the twisted cord from the last named balloon at a rate synchronized with the rate of twisting of the threads together, the positive withdrawing of the cord from the last named balloon serving as the sole power for drawing the threads from their balloons, for overcoming the retarding force imposed on them at their point of gathering, and for withdrawing the cord from its balloon, and yieldingly coiling such cord, the first twisting, the gathering, and the second twisting steps being performed with the material continuously in motion.

14. In combination in a strand-forming machine, means for supplying a plurality of strands, means having a spindle for doubling the strands into a plied strand, means associated with the doubling means for drawing the plied strand at a linear rate in a predetermined ratio to the speed of the spindle, and retarding means positioned between the supply means and the doubling means for tensioning the strands and disposed to receive the strands individually and to discharge them as a group, said drawing means being the sole means for drawing the strands from their sources and into the doubling means.

15. In combination in a strand-forming machine, means for supplying a plurality of strands, individual strand-tensioning means associated with each supply means, means having a spindle for doubling the strands into a plied strand, means associated with the doubling means for drawing the plied strand at a linear rate in a predetermined ratio to the speed of the spindle, and retarding means positioned between the strandtensioning means and the doubling means for tensioning the strands and disposed to receive the strands individually and to discharge them as a group, said drawing means being the sole means for drawing the strands from their sources and into the doubling means.

16. A combination as defined in claim 34 in which the retarding means comprises a rotatable roll driven solely by the strands and braking means for retarding the rotation of the roll.

17. In combination in a strand-forming machine, a plurality of singles twisters, means having a rotatable spindle for doubling a plurality of strands into a plied strand, tension-producing retarding means positioned for collecting strands passing from the twisters to the doubler into a group and discharging them as a group, means mounted on the doubling means for drawing the strands thereinto, and means for driving the drawing means from the spindle in a predetermined constant ratio to the spindle speed, said drawing means being the sole means for drawing the strands from the singles twisters and into the doubling means.

18. In combination in a strand-forming machine, a plurality of singles twisters, a tension device associated with each twister for tensioning each strand individually as it is discharged from the twister, means having a rotatable spindle for doubling a plurality of strands into a plied strand, tension-producing retarding means positioned for collecting strands passing from the tension devices to the doubler into a group and discharging them as a group, means mounted on the doublin means for drawing the strands thereinto, and means for driving the drawing means from the spindle in a predetermined constant ratio to the spindle speed, said drawing means being the sole means for drawing the strands from the singles twisters and into the doubling means.

19. A combination as defined in claim 18 in which the retarding means comprises a rotatable roll driven solely by the strands and braking means for retarding the rotation of the roll.

20. A combination as defined in claim 19 in which each of the twisters and the doubling means is of the two-for-one type.

JOSEPH A. TRUITT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 671,101 Bek Apr. 2, 1901 691,797 Norman Jan. 28, 1902 723,178 Norman Mar. 17, 1903 1,858,528 Somerville May 17, 1932 2,053,645 Weaver Sept. 8, 1936 2,410,674 Nelson Nov. 5, 1946 2,487,837 Uhlig Nov. 15, 1949 

